package cn.tedu.boot02.controller;

import cn.tedu.boot02.entity.Product;
import cn.tedu.boot02.utils.DBUtil;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;

@RestController
public class ProductController {
    @RequestMapping("/insert")
    public String insert(Product product) {
        System.out.println("product = " + product);

        try (Connection conn = DBUtil.getConnection();) {
            String sql = "INSERT INTO product VALUES(NULL,?,?,?)";

            //创建执行SQL语句的对象
            PreparedStatement ps = conn.prepareStatement(sql);

            //替换掉里面的?
            ps.setString(1, product.getTitle());
            ps.setDouble(2, product.getPrice());
            ps.setInt(3, product.getNum());

            //执行SQL语句
            ps.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return "添加成功！<a href='/'>返回首页</a>";
    }

    @RequestMapping("/select")
    public String select() {
        //创建集合用来装查询到的所有商品对象
        ArrayList<Product> list = new ArrayList<>();

        try (Connection conn = DBUtil.getConnection();) {
            String sql = "SELECT id,title,price,num FROM product"; //准备查询的SQL语句 id,title,price,num
            PreparedStatement ps = conn.prepareStatement(sql); //创建执行SQL语句的对象
            ResultSet rs = ps.executeQuery(); //执行查询SQL,得到结果集对象
            while (rs.next()) {
                Product product = new Product();
                product.setId(rs.getInt("id"));
                product.setTitle(rs.getString("title"));
                product.setPrice(rs.getDouble("price"));
                product.setNum(rs.getInt("num"));
                list.add(product); //把对象装进集合
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

        //return list.toString(); //用于测试是否能接收到添加的商品数据

        //把查询到的商品数据装进一个表格标签里面
        String html = "<table border=1>";
        html += "<caption>商品列表</caption>";
        html += "<tr><th>id</th><th>标题</th><th>价格</th><th>库存</th><th>操作</th></tr>";
        for (Product p : list) {
            html += "<tr>";
            html += "<td>" + p.getId() + "</td>";
            html += "<td>" + p.getTitle() + "</td>";
            html += "<td>" + p.getPrice() + "</td>";
            html += "<td>" + p.getNum() + "</td>";
            html += "<td><a href='/delete?id=" + p.getId() + "'>删除</a></td>";
            html += "</tr>";
        }
        html += "</table>";
        return html;
    }

    @RequestMapping("/delete")
    public String delete(int id) {
        System.out.println("id = " + id);
        try (Connection conn = DBUtil.getConnection();) {
            String sql = "DELETE FROM product WHERE id = ?";
            PreparedStatement ps = conn.prepareStatement(sql);
            ps.setInt(1, id);
            ps.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return "删除成功！<a href='/select'>返回列表页面</a>";
    }

    @RequestMapping("/update")
    public String update(Product product) {
        try (Connection conn = DBUtil.getConnection();) {
            String sql = "UPDATE product SET title=?,price=?,num=? WHERE id=?";
            PreparedStatement ps = conn.prepareStatement(sql);
            ps.setString(1, product.getTitle());
            ps.setDouble(2, product.getPrice());
            ps.setInt(3, product.getNum());
            ps.setInt(4, product.getId());
            ps.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return "修改完成!<a href='/select'>返回列表页面</a>";
    }
}
